Machining Performance of PM Material Containing MnX Additives

1999 ◽  
Author(s):  
S. Barnes ◽  
M. J. Nash ◽  
M. H. Lim

Abstract Improvements in the machining performance of ferrous powder metallurgy (PM) materials has recently been reported by one of the main manufacturers of metal powders. This improvement in machinability reportedly being achieved by the addition of a new free-machining additive which is marketed under the trade name of “MnX”. The work reported here, investigated this claim by comparing the performance of three PM materials with the same basic composition but different free-machining additives. The first material contained no free-machining additive, the second, contained the conventional manganese sulphide (MnS) additive and the third contained the new MnX additive. A turning operation was used to compare the performance of the three materials at cutting speeds in the range of 100–250 m/min using titanium nitride (TiN) coated UE6005 carbide inserts. The relative performance of the three materials was compared by measuring cutting forces, tool wear and the surface finish produced on the workpiece. It was found that at all cutting speeds investigated, the material containing MnX gave a superior performance. However, at higher cutting speeds the superiority of the material containing MnX was much more significant. In contrast, at the lowest cutting speed of 100 m/min, it was found that although the material containing MnX continued to exhibit the best performance, the differences between the three materials were substantially reduced and the material containing no free machining additive actually generated slightly less wear than the material containing MnS. The results therefore confirm that the new MnX additive is superior to the conventional MnS additive. However, this work has also demonstrated that relatively high cutting speeds are needed in order to obtain optimum benefits from the new additive.

2000 ◽  
Vol 122 (4) ◽  
pp. 379-383 ◽  
Author(s):  
Stuart Barnes ◽  
Michael J. Nash ◽  
Moh. H. Lim

A new free-machining additive, MnX, has been reported to improve the machining performance of ferrous powder metallurgy (PM) materials. This work investigated this claim by comparing the performance of three otherwise identical PM materials containing: no additive, conventional manganese sulphide (MnS) additions and the new MnX additive. A turning operation and cutting speeds of 100–250 m/min were used during which cutting forces, tool wear and surface finish were measured. The MnX material was found to exhibit superior performance. However, this was most noticeable at higher cutting speeds and at the lower cutting speeds, differences in performance were substantially reduced. [S0094-4289(00)02004-1]


2015 ◽  
Vol 1119 ◽  
pp. 617-621
Author(s):  
Mohsen Marani Barzani ◽  
Ahmed A.D. Sarhan ◽  
Saeed Farahani ◽  
Ramesh Singh

In this study, an experimental investigation was conducted to determine the effects of cutting speeds and feed rates on surface roughness in turning of the Al %11Si and Al-11%Si-1% Bi die cast alloys. Experimental trials carried out on a CNC machine using coated carbide inserts (PVD). Three different cutting speeds, 70, 130 and 250 m/min and three feed rates 0.05, 0.1 and 0.15 mm/rev were used with a 0.15 mm constant depth of cut for all experiments. Additionally scanning electron microscope (SEM) was employed to clarify the different types of silicon morphology. Results revealed that surface roughness increased with increasing feed rate from 0.05 to 0.15 mm/rev and decreased with increasing cutting speed from 70 to 250 m/min. The result showed that workpiece containing Bi had the best surface roughness with lamellar silicon shape in comparison with aluminium-silicon with flake-silicon shape.


2012 ◽  
Vol 565 ◽  
pp. 454-459 ◽  
Author(s):  
Yun Chen ◽  
Huai Zhong Li ◽  
Jun Wang

Titanium alloys are difficult-to-cut materials. This paper presents an experimental study of the effects of different cutting conditions and tool wear on cutting forces in dry milling Ti6Al4V with coated carbide inserts. The experimental results show that the peak forces increase with the increase in the feed rate and depth of cut. With the cutting speed increment in the range from 50 m/min to 150 m/min the peak forces decrease, while at further higher cutting speeds investigated peak forces increase. The decrease of the peak forces is due to thermal softening of the workpiece material and the increase is because of the strain hardening rate of Ti6Al4V. The tool wear experiment reveals that the major tool wear mechanism is the flank wear. The variations of the peak forces are caused by both the tool wear propagation and the thermal effects.


2012 ◽  
Vol 565 ◽  
pp. 370-375 ◽  
Author(s):  
Jun Shinozuka ◽  
Hidenobu Yachi ◽  
Tappei Higashi ◽  
Masato Sando ◽  
Toshio Maetani ◽  
...  

Orthogonal cutting experiment of powder metallurgy steel was performed in cutting speeds ranging from 1 m/s to 150 m/s. High-speed cutting experiment was carried out with a high-speed impact-cutting tester. This study focuses on the change in the effects of free-cutting of manganese sulfide with cutting speed. The principal force and thrust force were measured. The cross sections of the chip and of the machined surface were observed. Color mapping analysis of the tool-chip contact region on the rake face with EPMA was done. Although the serrated type of chip formed in all experiments, the cutting mechanism was analyzed by employing a shear plane model. This paper discusses how the effect that MnS promotes the ductile fracture and the effect that MnS improves the friction property at the tool-chip interface change as the cutting speed increases.


Author(s):  
M.G. Yagodin ◽  
E.I. Starovoytenko

The equipment for the production of wide range of metal powders purposed for powder metallurgy is described. The possibility for producing of powders by the plasma centrifugal spraying is considered taking into account the gas dynamic pressure. The calculated data on the powder size for different materials are given.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4046
Author(s):  
Mateusz Bronis ◽  
Edward Miko ◽  
Lukasz Nowakowski

This article discusses the relationship between the kinematic system used in drilling and the quality of through-holes. The drilling was done on a CTX Alpha 500 universal turning center using a TiAlN-coated 6.0 mm drill bit with internal cooling, mounted in a driven tool holder. The holes were cut in cylindrical 42CrMo4 + QT steel samples measuring 30 mm in diameter and 30 mm in length. Three types of hole-drilling kinematic systems were considered. The first consisted of a fixed workpiece and a tool performing rotary (primary) and linear motions. In the second system, the workpiece rotated (primary motion) while the tool moved linearly. In the third system, the workpiece and the tool rotated in opposite directions; the tool also moved linearly. The analysis was carried out for four output parameters characterizing the hole quality (i.e., cylindricity, straightness, roundness, and diameter errors). The experiment was designed using the Taguchi approach (orthogonal array). ANOVA multi-factor statistical analysis was used to determine the influence of the input parameters (cutting speed, feed per revolution and type of kinematic system) on the geometrical and dimensional errors of the hole. From the analysis, it is evident that the kinematic system had a significant effect on the hole roundness error.


2021 ◽  
Vol 14 (16) ◽  
Author(s):  
Adnan A. Ismael ◽  
Saleh J. Suleiman ◽  
Raid Rafi Omar Al-Nima ◽  
Nadhir Al-Ansari

AbstractCylindrical weir shapes offer a steady-state overflow pattern, where the type of weirs can offer a simple design and provide the ease-to-pass floating debris. This study considers a coefficient of discharge (Cd) prediction for oblique cylindrical weir using three diameters, the first is of D1 = 0.11 m, the second is of D2 = 0.09 m, and the third is of D3 = 0.06.5 m, and three inclination angles with respect to channel axis, the first is of θ1 = 90 ͦ, the second is of θ2 = 45 ͦ, and the third is of θ3 = 30 ͦ. The Cd values for total of 56 experiments are estimated by using the radial basis function network (RBFN), in addition of comparing that with the back-propagation neural network (BPNN) and cascade-forward neural network (CFNN). Root mean square error (RMSE), mean square error (MSE), and correlation coefficient (CC) statics are used as metrics measurements. The RBFN attained superior performance comparing to the other neural networks of BPNN and CFNN. It is found that, for the training stage, the RBFN network benchmarked very small RMSE and MSE values of 1.35E-12 and 1.83E-24, respectively and for the testing stage, it also could benchmark very small RMSE and MSE values of 0.0082 and 6.80E-05, respectively.


2013 ◽  
Vol 551 ◽  
pp. 143-160 ◽  
Author(s):  
Ajit Pal Singh ◽  
Brian Gabbitas ◽  
De Liang Zhang

Powder metallurgy (PM) is potentially capable of producing homogeneous titanium alloys at relative low cost compared to ingot metallurgy (IM). There are many established PM methods for consolidating metal powders to near net shapes with a high degree of freedom in alloy composition and resulting microstructural characteristics. The mechanical properties of titanium and its alloys processed using a powder metallurgical route have been studied in great detail; one major concern is that ductility and toughness of materials produced by a PM route are often lower than those of corresponding IM materials. The aim of this paper is to review the fracture toughness of both PM and IM titanium alloys. The effects of critical factors such as interstitial impurities, microstructural features and heat treatment on fracture toughness are also discussed


Author(s):  
Y. J. Lin ◽  
Samir A. Khrais

The tribological influences of PVD-applied TiAlN coatings on the wear of cemented carbide inserts and the microstructure wear behaviors of the coated tools under dry and wet machining are investigated. The turning test was conducted with variable high cutting speeds ranging from 210 m/min to 410m/min. The analyses based on the experimental results lead to strong evidences that conventional coolant has a retarded effect on TiAlN coatings under high-speed machining. Microwear mechanisms identified in the tests through SEM micrographs include edge chipping, micro-abrasion, micro-fatigue, micro-thermal, and micro-attrition. These micro-structural variations of coatings provide structure-physical alterations as the measures for wear alert of TiAlN coated tool inserts under high speed machining of steels.


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